4 things:
1.) His Mental + Physical Dominance - He was the greatest combination of both that the league has ever seen. Imagine the clutchness & football skills of Tom Brady mixed with the freakish athleticism of Lamar Jackson? That was Michael Jordan and having the greatest per-game stats and clutch metrics further substantiate this.
2.) His Stretch of Invincibility - From 1991–1998, if he had a training camp, he won, and HE was always the primary reason. Time and time again, the challengers came. Time and time again, he defended his turf. Two 3-peats will never happen again.
3.) His Carpe Diem - He maximized every one of his chances. 24-0 with home court, 24-0 as the higher seed - if he had the weapons, he won, and that's all you can ask for. There were no underachievements on his resume. If he lost, it was to a superior team.
4.) His Transcendence - He was bigger than the game. In sum, he was a modern-day superhero that can only be understood by those who were there.
Jordan was the greatest combination of individual dominance + team success that the league has ever seen. That's why he's the GOAT 🐐.